Hydrophobic hydration: Inhomogeneous water structure near nonpolar molecular solutes

A potential of mean force (PMF) expansion is used to predict the water structure near nonpolar solutes having different shapes and molecular conformations. The decomposition of $n$-particle PMFs into pair and triplet contributions describes well the hydration of those solutes consisting of nonbonded clusters, but not covalently bonded molecules. Alternative proximity approximations are devised based on the local dependence of the water structure on solute shape and excluded volume. Accurate predictions obtained using these proximity approximations demonstrate that water organization is only locally sensitive to structural details of nonpolar solutes.